The Seven Quality Control Tools

The seven QC tools were first emphasized by Kaoru Ishikawa, professor of engineering at Tokyo University and father of quality circles. His original seven tools were:

Cause-and-effect Diagram	Check Sheets	Control Charts	Histogram
Pareto chart	Scatter Diagram	Stratification*

*Some lists replace stratification with flowchart or run chart.

They are variously called the seven quality control tools, the seven basic tools, or the seven old tools. Regardless of the name, a set of seven simple yet powerful tools are used in every system of quality improvement.